Moles
Moles are clusters of pigment cells in the skin. Most people have a few dozen, and they form mainly in childhood and youth. The great majority stay unchanged for life and are harmless.
The question when checking moles is therefore not how many you have, but whether any of them has changed and whether any stands out from all the others. The answer can often be found within a few minutes.
The ABCDE rule and the ugly duckling sign
Specialists use the ABCDE rule to help with the assessment. A stands for asymmetry, that is, a mole whose two halves do not look alike. B stands for an irregular, jagged or blurred border. C stands for uneven colour made up of several shades of brown, black, red or blue. D stands for a diameter over six millimetres, although smaller moles can also be dangerous. E stands for evolution, that is, change over time.
At home, the last criterion is the most useful. A mole that has changed in size, shape, colour or surface over the past few months should be examined.
The ugly duckling sign is just as useful. A person's moles usually look similar to one another; the one that is visibly different from all the others deserves an examination regardless of its size.
A mole that is changing is not something to watch. It is something to have examined. With melanoma, waiting for the next season or for the annual check-up is the costliest decision, as the disease is very curable at an early stage, but the chances diminish over time.
What increases the risk
The risk is higher in people with fair skin, light or red hair and freckles, in those with a large number of moles, and in those who had severe blistering sunburn in childhood.
Melanoma in a first-degree relative and a melanoma you have already had yourself are also important. The risk is increased by the use of sunbeds, working outdoors without protection and medicines that suppress the immune system.
The sun does harm through the total dose and through burns. That is exactly why protection matters outside summer too, and also for people who do not deliberately sunbathe.
When not to delay
Book an appointment as a priority if a mole bleeds without being injured, if it keeps itching or burning, if a scab or small sore has appeared on it that has not healed for several weeks, if it has grown quickly, or if a new dark mole has appeared after the age of forty.
The same applies to a dark streak that has appeared under a nail and does not move as the nail grows, and to a change on the sole, palm or a mucous membrane. These areas are the ones most often forgotten during self-examination.
Some skin conditions are emergencies. If you have a rapidly spreading rash with fever and feeling unwell, blisters over large areas of skin, involvement of the mucous membranes in the mouth or eyes, or swelling of the face and lips with difficulty breathing, call 112.
A suspicious mole is not a reason to call 112, but it is a reason not to postpone your appointment. No wait between examination and removal is worth prolonging.
What the examination involves
The dermatologist examines the skin systematically, including areas you cannot see yourself: the back, the scalp, behind the ears, between the toes and on the soles of the feet. Individual moles are examined with a dermatoscope, a magnifying and illuminating device that shows the structure beneath the surface of the skin. The examination is painless and involves no radiation.
Some moles are documented with a photograph so that an accurate comparison is possible at the next examination. With moles, comparison over time is often more decisive than a one-off assessment.
When a change is suspicious, the dermatologist recommends removal and histological examination. The procedure is carried out under local anaesthetic, and the removed tissue is examined by a pathologist. The report says what it was and whether the removal was complete.
Come to the examination without make-up and without nail varnish, and do not cover your moles with plasters beforehand. If you have recently spent a lot of time in the sun, mention it when booking, as a tan makes it harder to assess colour and borders.
How to protect yourself
The most effective protection is not a cream but avoiding the sun during the part of the day when the UV index is highest (usually between 11 am and 3 or 4 pm), shade, a hat and clothing. A cream with a high protection factor is an addition; enough of it must be applied, and reapplied every two hours and after swimming.
A sunbed does not prepare the skin for the sun and does not reduce the risk. On the contrary, it increases the risk, especially with exposure at a young age.
Look over your skin yourself once a month, ideally in good light and with a mirror, and ask someone close to you to check your back and scalp. You are looking for a change compared with the previous month, not for perfection.